DCP going south??

NavLinear

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#44
Little up date got the the carver tecs house around 1/4 past 10 this morning he has all the happy equipment for this sort of work.. he worked on it till around 2 this afternoon he said he had other things that need to be done this afternoon he is not sure what is ailing it so I left it with him.. if he can't find the problem with it with all his happy equipment then I figure I stand 0 chance of nailing it down with just my simple scope and DMM... so that is how that went

Think I'll shut the shop down now and go in the house with my tail between my legs it's been a bad week......
We've all been there - all will get better with some help. A nurse is on the way. It will only hurt for a second - I promise. :confused1:
 

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roccus

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#46
We've all been there - all will get better with some help. A nurse is on the way. It will only hurt for a second - I promise. :confused1:
Oh my on one hand I want to let her administer anything she's got on the other hand I want to run away as fast as I can!! lol
 

roccus

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#49
Like Joe says, "yep, it means something" but not ready to say it's the DCP itself. Are you watching the DC level on the outputs as you bring up more and more voltage? From memory (forgive me Joe lol) I would say that with around 30 volts on the rails, the outputs should be zero'd out by then. If both channels are good and stable by 50 volts or so and the relay still hasn't kicked in, then yeah.. something's up with the DCP perhaps..
Finally catching up on stuff around here and am going back to the 400 to try some of the tests sent to me here... one question I had the was never answered was about step 8 in the DCP manual...

"8. If a signal generator is available insert a 1KHZ sine wave into the left channel. Set the
generator level to obtain 40 VAC on the amplifier output."

I do not have a signal generator that can apply voltage all I have an app to run out of my laptop. Would it be the same if I just put 40V to the amp with a variac then apply 1Khz from my laptop to get same results?

On JB's test

Left channel - I bring up voltage watching DC on the outputs at 30V .003mv dc at outputs it stays at .003mv at 50V no relay kick in... relay kicks in at 75V AC, DC on output goes to .138mv then .121mv DC at output at 115V AC from the variac

Right channel - at 30V .008mv at output at 50V no change still .008mv still no relay kick in 75V relay kicks in .135mv DC at output then .115mv DC at outputs with 115V fed in from variac
 

laatsch55

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#53
Actually 75mv on a stocker, a WOPL is less than 10..when checking offset there should be no amp input...nothing hooked to the RCA jacks. Have you replaced the 1237's??
 

WOPL Sniffer

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#56
I must have missed the part about coming back from the "Carver Tech's" shop. First things we check are the offset and the bias. If either is FU, we fix, not jam for a month. I would NEVER have attached this to one of my speakers. 130-140 mv is jacked. WOPL or no WOPL.

I had 1mv on the last amp and didn't like it.
 

laatsch55

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#60
The II'S had an IC front end, the preceding had a discreet front end. With a little TLC a guy can get a discreet front end below 10.
 
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